It will happen during his upcoming trip to the UK.

From the Guardian:

Pope Benedict’s arrival in Britain breaks new ground on many levels, with a state welcome from the Queen and the beatification of Cardinal Henry Newman. But buried in the itinerary is another and, some would say, more piquant landmark.

Next Friday, the pope will meet the Rev Jane Hedges, canon steward of Westminster Abbey and a campaigner for women bishops in the Church of England. It will be the first time the head of the Vatican, which earlier this year declared female ordination a “crime against the faith”, shakes hands with a clergywoman.

Their meeting will act as a reminder of the differences and difficulties between the Anglican Communion and the Roman Catholic church. The abbey team is aware of the many historic aspects to the visit.

“We shall greet this pope as our guest. There will no hint of battle,” wrote the dean of Westminster, the Very Rev Dr John Hall, last week in the Tablet, a weekly Catholic newspaper.

An ecumenical evensong will begin with an exchange of peace between the archbishop of Canterbury and Benedict XVI, and include a psalm, the Magnificat, readings and prayers. “I have no doubt that it will be a memorable occasion. Yet it will also be coloured by many emotions,” Hall said.

You can read more at the link.